hwpf: IndexOutOfBoundsException in Range.findRange when list contains only nulls

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1036850 13f79535-47bb-0310-9956-ffa450edef68

src/scratchpad/src/org/apache/poi/hwpf/usermodel/Range.java

@@ -973,6 +973,11 @@ public class Range { // TODO -instantiable superclass
 
 		while (node==null || (node.getEnd() <= start && x < rpl.size() - 1)) {
 			x++;
+
+            if (x>=rpl.size()) {
+                return new int[] {0, 0};
+            }
+
 			node = rpl.get(x);
 		}